Donald Trump on Sunday restated his support for Roy Moore, the Republican Alabama Senate candidate who is accused of sexual misconduct with four women, one of whom was 14 when the incident is alleged to have occurred.

In response, Republican senators said Trump was wrong to make a “political” decision to back Moore, rather than take into account the “character of our country”.

Referring to the Democrat Doug Jones, who is marginally ahead in the deep red state, Trump tweeted: “The last thing we need in Alabama and the US Senate is a Schumer/Pelosi puppet who is WEAK on Crime, WEAK on the Border, Bad for our Military and our great Vets, Bad for our 2nd Amendment, AND WANTS TO RAISES TAXES TO THE SKY. Jones would be a disaster!”

Referring to the appointed incumbent, Trump added: “I endorsed Luther Strange in the Alabama Primary. He shot way up in the polls but it wasn’t enough. Can’t let Schumer/Pelosi win this race. Liberal Jones would be BAD!”

Trump did not use Moore’s name but the New York Times reported on Saturday that the president has compared the accusations against the Alabama judge to those against him that arose from the release last October of a 2005 Access Hollywood tape, in which the then businessman was heard to boast about sexually assaulting women.

The Times said the president had told a senator and an adviser he now thinks the tape is “not authentic”. At the time of its release, Trump acknowledged that the voice on the tape was his, and apologised.

Moore denies the allegations against him, which date from 30 to 40 years ago and were first reported by the Washington Post. He has defied the Republican establishment in Congress to stay on the ballot and found support from Steve Bannon, Trump’s former White House strategist, and the president himself.

The South Carolina senator Lindsey Graham was asked on CNN’s State of the Union on Sunday if Trump was wrong to back a candidate one reporter speaking to the president this week called an “accused child molester”.

“That’s a political decision by the president,” he said. “From a Republican point of view, I don’t see what winning looks like with Roy Moore. If he wins, we get the baggage of him winning and it becomes a story every day about whether or not you believe the women or believe Roy Moore, should he stay in the Senate or should he be expelled.

“If you lose, you give the Senate seat to a Democrat at a time when we need all the seats we can get.”

The election to fill the seat vacated by the US attorney general, Jeff Sessions, is on 12 December. Republicans hold a 52-48 majority in the Senate, with which they hope to pass tax-cut legislation which Graham said meant “the fate of the party is at stake as well as the [US] economy”.

“The moral of the story is don’t nominate someone like Roy Moore who could actually lose a seat that any other Republican could win,” Graham said. “And from a party perspective, we’ve got to look long term, not short term. I would tell President Trump, if you think winning with Roy Moore is going to be easy for the Republican party, you’re mistaken.”

“The reality of it is that the allegations are still very strong, and credible, and the denial has been very weak. [It’s] gotten a little stronger but in my opinion and the opinion of a lot of conservatives and Republicans in the Senate it is time to turn the page because it is not about partisan politics or electing Republicans versus Democrats, it is about the character of our country.

“I want to be on the side of right when history writes its story.”

John Thune of South Dakota told Fox News Sunday it would be in Alabama’s “best interest, and in the country’s best interest and certainly the best interest of our agenda if the president would use his influence to try to get Roy Moore to step aside”, in favour of a write-in candidate.

On Saturday an Alabama sporting great, the NBA Hall of Famer Charles Barkley, added his voice to the chorus against Moore, saying he should not have been in the running before the sexual misconduct allegations because of his links to Bannon, who Barkley said was a “white separatist”.